1. Field of the Invention
The present invention relates to V-Belt drives and more particularly to a method of controlling the speed of a driven shaft not withstanding variations in the speed of a driver shaft.
2. Description of Background Art
A V-Belt power transmission drive including a driver pulley, a driven pulley and a V-belt interconnecting the pulleys is a common method of transmitting torque from a prime mover to a load. While the angular velocity i.e., rotational speed, of the driven pulley is normally not equal to the rotational speed of the driver pulley, as determined by the ratio of the circumference of the driven pulley to the circumference of the driver pulley, the speed of the driven pulley is normally directly proportional to the speed of the drive pulley.
One use of such V-belt drives is in driving the generator of a vehicle. Such generators conventionally have optimal operating speeds. The generator is driven from the automobile engine, the speed of which varies, so that the speed of the generator correspondingly varies.
Therefore, in such operation of the vehicle, the generator may not be operating at the optimal speed at all times and must be designed to operate over a wide range of driven speeds.
In other applications incorporating V-belt transmissions, the prime mover has a speed-versus-torque relationship different from the speed-versus-torque relationship of the load. Where the speed of the load is caused to be directly proportional to the speed of the prime mover, the prime mover must be sufficiently oversized to permit the torque output of the prime mover at any speed to satisfy the torque requirement of the load at the operating speed thereof. Such oversizing is undesirable for economic concerns, space requirements, ease of maintenance, etc.